The title is the accusation/declaration hurled by a mercurial bunny who's peeved that he's been made to wait for readers to show up. "Do you know how RUDE it is to make me wait?" demands the bunny of his audience, as Watt splits her page into four instructional frames. "As rude as talking with my mouth full... As rude as sticking gum under the sofa... As rude as running on carpet with muddy feet... As rude as making faces behind someone's back." (Perceptive readers will recognize that many of the bunny's similes feature common childhood transgressions.) But the bunny, vacillating between anger and apology, is hardly a paragon of polite behavior ("BUT SERIOUSLY, WHERE WERE YOU?" he screams, just one page after cheering readers with a cake, banner, pennant, and dance). And like the rest of the world, he can't resist taking a phone call ("Sure, I'm free to talk—they can wait"). Combining Watt's considerable gifts for metanarrative, social satire, outsize characters, and manic cartooning in one wonderfully silly tale, this is another keeper from a consistently funny talent. Ages 3–6. (Mar.)